Re-Ripping my CD's : what's with the audio level measurement?

[Bucknekked]

Fun fact that I just learned. You can change the volume of individual files by going to the options tab:

As for iTunes itself, I use a Mac and really it works great on a Mac. I haven't used iTunes on Windows in years but I remember it was not a good experience. I would imagine that most people that hate iTunes have only used it on Windows.

Yes, you can adjust the volume (up or down) for each song individually or entire album with iTunes. I should warn that that saying out loud that you like iTunes and use it will expose you to possible unsolicited opinions about your parentage, your scholastic ability, and perhaps other aspects of your life you may have thought were unaffected by using iTunes. I too use iTunes and after public flogging, I now avoid saying it out loud unless I can't find a way around it. The other kids can be mean on the playground

 

[PietjePuk]

shhhhhhh. Don't say "isn't ripping just making a 1 on 1 copy?" in a forum with audiophiles lurking about. You'll probably set one of them off on a rant on how one method, although there's no technical differences, sounds better than another to their "golden ears". Dear, or dear, I'd hate to see a newb run down and trampled.

Just as a PERSONAL OPINION, making a bit perfect copy of a CD in to a digital library is pretty much what ripping CD's should be all about. Its been my experience if one of the genuine enthusiasts hears that, there's a rant coming on .

MusicBrainz makes good stuff.

Haha thanks for the warning Luckily it's the interwebs so I can hide... Let the rants begin!

 

[slipperybidness]

shhhhhhh. Don't say "isn't ripping just making a 1 on 1 copy?" in a forum with audiophiles lurking about. You'll probably set one of them off on a rant on how one method, although there's no technical differences, sounds better than another to their "golden ears". Dear, or dear, I'd hate to see a newb run down and trampled.

Just as a PERSONAL OPINION, making a bit perfect copy of a CD in to a digital library is pretty much what ripping CD's should be all about. Its been my experience if one of the genuine enthusiasts hears that, there's a rant coming on .

MusicBrainz makes good stuff.

No rant here.

BUT......are you CERTAIN that your rips are really exact bit-for-bit copies to the original? I'm not sure of the capabilities for iTunes/Mac

That is why I use EAC. It doesn't JUST make the copy, it also checks the copy against known-good rips and gives you feedback that the copy is bit-perfect (or not).

 

[slipperybidness]

Yes, you can adjust the volume (up or down) for each song individually or entire album with iTunes. I should warn that that saying out loud that you like iTunes and use it will expose you to possible unsolicited opinions about your parentage, your scholastic ability, and perhaps other aspects of your life you may have thought were unaffected by using iTunes. I too use iTunes and after public flogging, I now avoid saying it out loud unless I can't find a way around it. The other kids can be mean on the playground

Well, at least you learned that lesson. We learn you good around these parts.

To be clear, those of us that have a dislike for iTunes--we all have good reasons for that, used it, hated it moved along to better options (for our particular wants and needs).

 

[sterling shoote]

Hey, if you make your choice then you live with it, no problem. I just wanted to be sure that you weren't "iTunes by default" and never explored any other options.

I'm 100% FOOBAR2000 fanboy!

I started using iTunes with my old 20Gb iPod, then with my iPhone. Then, I got enough sense to swap to Android and FOOBAR

Interestingly enough, the developer of Foobar says all players sound the same.

 

[sterling shoote]

All, I use iTunes on Windows. I like it. I like it a lot. Just today I created a CD from an LP I just purchased, John Coltrane Best of 1957 - 1962. When I digitized the LP, I set the recording level off the LP's first tune; and, I did not increase or decrease the level from that point. After producing the CD, I ripped it to iTunes. Now, here's the volume level per selection: +9.2db, +7.6db, +7.6db, +7.9db, +10.6db, +7.3db, +11.0db, +9.7db, +9.8db, +9.8db, +10.2db. I cannot sense, except at a very, very low volume that the volume between selections has gone up or down. I suspect if I had a playlist with gross volume divergence between selections I might want to set "sound check"; but, so far with over 6000 songs in my iTunes library, I have not heard a need to turn on that function.

 

[Bucknekked]

All, I use iTunes on Windows. I like it. I like it a lot. Just today I created a CD from an LP I just purchased, John Coltrane Best of 1957 - 1962. When I digitized the LP, I set the recording level off the LP's first tune; and, I did not increase or decrease the level from that point. After producing the CD, I ripped it to iTunes. Now, here's the volume level per selection: +9.2db, +7.6db, +7.6db, +7.9db, +10.6db, +7.3db, +11.0db, +9.7db, +9.8db, +9.8db, +10.2db. I cannot sense, except at a very, very low volume that the volume between selections has gone up or down. I suspect if I had a playlist with gross volume divergence between selections I might want to set "sound check"; but, so far with over 6000 songs in my iTunes library, I have not heard a need to turn on that function.

sterling,
Area the db levels you quotes (+)db levels or (-)db levels? When I looked at my songs, without ever touching a starting point volume, all the listed song db levels were (-). The highest level I saw was 0.0db. All the rest were between -.1 to -10.1. Just interested to see if this was a typo, or your song levels really are above 0db

 

[slipperybidness]

Interestingly enough, the developer of Foobar says all players sound the same.

Perhaps, but I never mentioned anything about FOOBAR for sound quality. It's the user interface and the user customization that makes it my player of choice.

 

[sterling shoote]

that sounds like something someone NOT on a forum would

sterling,
Area the db levels you quotes (+)db levels or (-)db levels? When I looked at my songs, without ever touching a starting point volume, all the listed song db levels were (-). The highest level I saw was 0.0db. All the rest were between -.1 to -10.1. Just interested to see if this was a typo, or your song levels really are above 0db

No typo, on today's CD which are quite compressed, I see that the levels are, for the most part, (-). Many of my CD's were burnt from LP's.

 

[sterling shoote]

Perhaps, but I never mentioned anything about FOOBAR for sound quality. It's the user interface and the user customization that makes it my player of choice.

Yes, Indeed!

 

[Bucknekked]

No rant here.

BUT......are you CERTAIN that your rips are really exact bit-for-bit copies to the original? I'm not sure of the capabilities for iTunes/Mac

That is why I use EAC. It doesn't JUST make the copy, it also checks the copy against known-good rips and gives you feedback that the copy is bit-perfect (or not).

slipperybidness
Certain? Probably more comfortable than certain. I did a couple of CD's with XLD and iTunes. Listened to the songs and could hear no difference. Looked at a few file sizes and they matched. There's quite a bit of discussion on the value of bit perfect out on the web. Some folks don't give it much value, others of course find it to be the holy grail.

But to be fair, my sample size was small and all my CD's are virtually brand new. Most of my CD's were purchased, ripped in, then put in a sleeve in a binder and put in a safe. Many folks find much to their surprise that iTunes will successfully rip used/scratched CD's that other "bit perfect" programs give up on because of errors. ITunes error recovery is pretty robust.

I may do a test over the weekend now that you have mentioned the bit perfect comparison. I am thinking about buying some new CDs. I may do a rip and compare test to see what comes of those. XLD and iTtunes.

 

[Bucknekked]

No typo, on today's CD which are quite compressed, I see that the levels are, for the most part, (-). Many of my CD's were burnt from LP's.

interesting.
Audio volume levels above 0.0, are bad news from a recording point of view. I guess this means we simply have no idea what that metric is trying to tell us.

I just saw that you said "many of my CD's were made from LPs". That means a lot !
Professional recording engineers take a lot of time and trouble to make sure volume levels never top out over 0.0db. They leave headroom. If you recorded these CD's from LPs, you may have set the recording levels high enough that you are indeed hitting levels over 0db.

 

[sterling shoote]

interesting. If you see (+) db volume levels on some CD's and songs, and (-) db levels on other CD's and songs, that means we truly have no idea what that volume level statistic means. If it was true, there would be an audible difference track to track. There doesn't seem to be. Neither of us uses "sound check" to tell iTunes to level the volume from track to track. So the CD itself has already been leveled.

Audio volume levels above 0.0, are bad news from a recording point of view. I guess this means we simply have no idea what that metric is trying to tell us.

Well, yes the LP was leveled by the recording eng. I assume. So, what ever we get from selection to selection is perhaps an indication of how the selections collectively or individually were mastered to CD or LP. The album I converted to CD was produced from tapes produced from 1957 to 1962.

 

[Bucknekked]

No rant here.

BUT......are you CERTAIN that your rips are really exact bit-for-bit copies to the original? I'm not sure of the capabilities for iTunes/Mac

That is why I use EAC. It doesn't JUST make the copy, it also checks the copy against known-good rips and gives you feedback that the copy is bit-perfect (or not).

slipperybidness:
I bought a new CD, one that is pretty much guaranteed to be in the AccurateRip database, and did a test this evening by ripping it with iTunes, XLD in Secure mode, and XLD in CDParanoia mode.
I didn't expect this result, but the copies from iTunes and XLD do have small differences in file size.
Playing the files shows no difference to the ear, there are no imperfections in any of the rips.
But, the fact there are small file size differences is not what I expected to see.

Furthermore, in XLD's two modes, Secure and CDParanoia, they produce exactly the same file results on multiple passes. They also give a confidence level against AccurateRip database for the same song/artiste. I do not understand the format of the confidence level . It looks like 215/679.

I shall now have to pause and think about what I have just learned. iTunes certainly can rip it faster and there's no audible difference I can detect. Conversely, XLD can give me the exact same byte count time after time and compare it to a national database. If the comparison is only 215/679 matches, that isn't saying iTunes isn't pegging a value of 500/679, its just there is no external comparison point at all.

I don't know that I have a value judgement on what I just learned just yet. But, I will say this slipperybidness, I did not expect this as a result. I am surprised. I must noodle on this for a bit.

 

[Bucknekked]

slipperybidness:
I don't know that I have a value judgement on what I just learned just yet. But, I will say this slipperybidness, I did not expect this as a result. I am surprised. I must noodle on this for a bit.

I have done some more noodling and reading on the aspect of bit perfect, iTunes, and other rippers like XLD. On the surface, the differences I saw ripping a CD this evening would say that somehow XLD is giving a more consistent and accurate rip. Not necessarily true however.

If I had the patience, I would do as this reviewer did, and run 10 consecutive rips. Then set all ten files up for a digital file compare. iTunes hit it dead on : 10 for 10 rips all bit identical. That's not to say that XLD couldn't do 10 for 10 just as well. The difference between the iTunes rip and the XLD rip may simply be the digital audio offset at the beginning of the CD: ie when does the application start recording music content?

The author of this article compares just that. Once XLD and iTunes begin recording, are the results bit identical after that? In his sample of 10 files done with each, they indeed were bit identical once the music began. Apparently, if one is really patient, and one has the time to lay the files out and do a very detailed compare, it all comes out in the end.

What I learned this evening is that unlike regular computer files in a traditional data file format, CD audio WAV files get laid down and read back up in a fairly unique way that doesn't guarantee read accuracy to the bit level. I am still trying to figure that out and get more data points. It seems to have something to do with the beginning track space and inter track space for the song to song gaps and the initial CD audio playback gap.

I guess that makes a very long winded way of saying, all this is a big surprise to me. I don't know that I have it figured out just yet. I certainly will disclaim any expertise here. There's more to know and understand that I have managed so far.

 

[sterling shoote]

I have done some more noodling and reading on the aspect of bit perfect, iTunes, and other rippers like XLD. On the surface, the differences I saw ripping a CD this evening would say that somehow XLD is giving a more consistent and accurate rip. Not necessarily true however.

If I had the patience, I would do as this reviewer did, and run 10 consecutive rips. Then set all ten files up for a digital file compare. iTunes hit it dead on : 10 for 10 rips all bit identical. That's not to say that XLD couldn't do 10 for 10 just as well. The difference between the iTunes rip and the XLD rip may simply be the digital audio offset at the beginning of the CD: ie when does the application start recording music content?

The author of this article compares just that. Once XLD and iTunes begin recording, are the results bit identical after that? In his sample of 10 files done with each, they indeed were bit identical once the music began. Apparently, if one is really patient, and one has the time to lay the files out and do a very detailed compare, it all comes out in the end.

What I learned this evening is that unlike regular computer files in a traditional data file format, CD audio WAV files get laid down and read back up in a fairly unique way that doesn't guarantee read accuracy to the bit level. I am still trying to figure that out and get more data points. It seems to have something to do with the beginning track space and inter track space for the song to song gaps and the initial CD audio playback gap.

I guess that makes a very long winded way of saying, all this is a big surprise to me. I don't know that I have it figured out just yet. I certainly will disclaim any expertise here. There's more to know and understand that I have managed so far.

This topic aroused my curiosity, so, this morning I experimented with a CD having an extreme amount of dynamic range. Ripping it to iTunes, I discovered a range from +1.0 to +17.4db per selection. Simply playing back these selections with sound check off I realized the "volume" notice in iTunes "file" is an indication of dynamic range, one of the selections I played having, it appears, +17.4db dynamic range. It also appears that -0.1 would have less dynamic range than let's say +0.1. Also, I ripped The Rolling Stones Steel Wheels CD and noticed it has less dynamic range than most other CD's ripped to iTunes. Even at extremely low playback levels I can hear all passages. Perhaps, that's why this CD is listenable in my Tahoe when there are all sorts of road noise distracting me as I drive down the highway. Now, all of my experimenting may be moot since ripping a CD to iTunes does not get more dynamic range. I don't think you could create less range either. Converting LP's to CD's on the other hand does allow for maximization of dynamic range at least to the extent it exists on the LP.

 

[highfigh]

All, I use iTunes on Windows. I like it. I like it a lot. Just today I created a CD from an LP I just purchased, John Coltrane Best of 1957 - 1962. When I digitized the LP, I set the recording level off the LP's first tune; and, I did not increase or decrease the level from that point. After producing the CD, I ripped it to iTunes. Now, here's the volume level per selection: +9.2db, +7.6db, +7.6db, +7.9db, +10.6db, +7.3db, +11.0db, +9.7db, +9.8db, +9.8db, +10.2db. I cannot sense, except at a very, very low volume that the volume between selections has gone up or down. I suspect if I had a playlist with gross volume divergence between selections I might want to set "sound check"; but, so far with over 6000 songs in my iTunes library, I have not heard a need to turn on that function.

Do you add a pause between tracks, or just save it as an album to be listened in its entirety? Part of me wants to record my LPs in the latter form, because that's how I listen to them but I have become accustomed to the amount of time between tracks, so creating a playlist of music from LPs might be a bit annoying (I want it and I want it NOW!).

 

[highfigh]

This topic aroused my curiosity, so, this morning I experimented with a CD having an extreme amount of dynamic range. Ripping it to iTunes, I discovered a range from +1.0 to +17.4db per selection. Simply playing back these selections with sound check off I realized the "volume" notice in iTunes "file" is an indication of dynamic range, one of the selections I played having, it appears, +17.4db dynamic range. It also appears that -0.1 would have less dynamic range than let's say +0.1. Also, I ripped The Rolling Stones Steel Wheels CD and noticed it has less dynamic range than most other CD's ripped to iTunes. Even at extremely low playback levels I can hear all passages. Perhaps, that's why this CD is listenable in my Tahoe when there are all sorts of road noise distracting me as I drive down the highway. Now, all of my experimenting may be moot since ripping a CD to iTunes does not get more dynamic range. I don't think you could create less range either. Converting LP's to CD's on the other hand does allow for maximization of dynamic range at least to the extent it exists on the LP.

17.4dB may be an extreme dynamic range now, but if you have a tape recorder, set it to record and pause it so you can watch the VU meters while you play a CD and LP of the same recording (preferably something that was originally released before CDs became available). I used to do that when CDs came out and often saw ~20dB dynamic range for CDs and almost 30dB for LPs. In recent years, because so many people had ear buds shoved in their ears and use hand-held devices for most of their listening, dynamics became a thing of the past and many articles have been published about it, including here at Audioholics. In some cases, dynamics had been reduced to about 6dB.

 

[John Passantino]

The volume adjustment is for Sound Check in iTunes. It does not change the audio file. It's just metadata for changing the volume during playback when Sound Check is turned on.

I use iTunes for all ripping to AIFF files with "Use error correction when reading Audio CDs" under Import Settings turned on. It's pretty much perfect as far as I can tell. I used to use EAC, but I didn't find the more complex workflow to be worth it.

 

[Bucknekked]

The volume adjustment is for Sound Check in iTunes. It does not change the audio file. It's just metadata for changing the volume during playback when Sound Check is turned on.

I use iTunes for all ripping to AIFF files with "Use error correction when reading Audio CDs" under Import Settings turned on. It's pretty much perfect as far as I can tell. I used to use EAC, but I didn't find the more complex workflow to be worth it.

I think I am agreeing with you on all points.
I will keep a log of rips in the next couple of weeks and compare iTunes in repetitive rips just to make sure I am getting what I believe I am getting. XLD is a good ripper but it is more prone to small problems for me. I will keep them both.